This invention relates to an attenuator that is used in, for example, a terminal end section of a high frequency transmission circuit, and is to attenuate an input signal.
In related art, an attenuator having a resistor has been used for suppressing unnecessary reflection of a signal or attenuating an input signal to be outputted, for example, at an end of a signal line of a high frequency circuit (for example, see Japanese Unexamined Patent Application Publication No. Hei6-104591). Such an attenuator is desired to have the following properties: downsized and simplified configuration; easiness of connection to a signal line; excellent heat dissipation ability at the time of being supplied with power and less deterioration in the ability due to heat (excellent power durability); constant characteristic impedance in a predetermined frequency band; and less and stable reflectance loss in a predetermined frequency band (excellent high frequency property).
For example, in Japanese Unexamined Patent Application Publication No. Hei11-55008, there is disclosed a power resistor for high frequency capable of obtaining necessary power durability without increasing an area of a resistor in proportion to a rated power value.